Cosentyx is typically taken once every 4 weeks as a long-term maintenance dose, but you’ll start with a more frequent loading phase: one injection per week for the first 5 weeks. The exact schedule depends on which condition you’re treating and how you respond.
The Standard Dosing Schedule
For most conditions Cosentyx treats, the pattern is the same. You take a 300 mg injection once a week for five consecutive weeks (at weeks 0, 1, 2, 3, and 4). After that initial loading phase, you switch to one injection every 4 weeks for as long as you stay on the medication. That every-4-weeks rhythm is the schedule most people settle into long term.
Each 300 mg dose can be given as a single injection or split into two 150 mg injections. For plaque psoriasis specifically, some patients do well on a lower 150 mg dose, which your prescriber may consider based on your response.
Dosing by Condition
The loading phase and maintenance frequency are the same across plaque psoriasis, psoriatic arthritis, ankylosing spondylitis, and hidradenitis suppurativa: weekly for five weeks, then every four weeks. The one notable exception is hidradenitis suppurativa. If you don’t respond well enough on the standard schedule, your doctor may increase the frequency to every 2 weeks instead of every 4.
For certain joint conditions like psoriatic arthritis and ankylosing spondylitis, an intravenous (IV) option also exists. The IV version uses a weight-based dose and can be given with or without a single loading infusion, followed by infusions every 4 weeks. Most people use the self-injected version at home, but the IV route is available for those who need it.
Dosing for Children and Teens
Children with plaque psoriasis follow the same weekly-then-monthly timing as adults. The difference is the dose, which is based on body weight. Kids under 50 kg (about 110 pounds) receive 75 mg per injection, while those over 50 kg get the same 150 to 300 mg range used in adults. The schedule remains weekly for five weeks, then every four weeks.
How Quickly Cosentyx Works
Don’t expect overnight results during the loading phase. In clinical trials for psoriatic arthritis, roughly 40% of patients saw meaningful improvement in joint symptoms by week 16. That improvement continued to build over time, with many patients reporting further gains through week 52 and even out to two years. Starting with the weekly loading doses did produce earlier responses on some measures compared to skipping the loading phase, which is one reason the loading schedule is standard.
For skin symptoms, the timeline is similar. Significant clearance tends to appear within the first few months, though it varies from person to person.
What to Do If You Miss a Dose
If you forget a dose, take it as soon as you remember, then contact your doctor to figure out when your next dose should fall. Don’t double up to compensate for the missed one. Getting back on a regular 4-week cycle matters, so your doctor can help you reset the schedule rather than guessing.
Storing Your Medication
Cosentyx needs to stay in the refrigerator between 36°F and 46°F (2°C to 8°C). It doesn’t contain preservatives, so once you pull a pen or prefilled syringe out of the fridge, you have just one hour to inject it. Don’t leave it sitting on a counter for later use. If you’re traveling, plan ahead with a cooler bag to keep it within the right temperature range.